diff --git a/lib/multipartform.js b/lib/multipartform.js
index 7196724..a744532 100644
--- a/lib/multipartform.js
+++ b/lib/multipartform.js
@@ -101,42 +101,49 @@ Part.prototype = {
   // with the whole Part
   // Calls the callback when complete
   write: function(stream, callback) {
-	
-    var self = this;
-	
-	  //first write the Content-Disposition
-	  stream.write(this.header());
-	
-  	//Now write out the body of the Part
-    if (this.value instanceof File) {
-  	  fs.open(this.value.path, "r", 0666, function (err, fd) { 
-    	  if (err) throw err; 
-    	  
-  		  var position = 0;
-  		  
-  	    (function reader () {
-  	      fs.read(fd, 1024 * 4, position, "binary", function (er, chunk) {
-  	        if (er) callback(err);
-  	        stream.write(chunk); 
-  	        position += 1024 * 4;
-  	        if (chunk) reader();
-  	        else {
-  			      stream.write("\r\n")
-      			  callback();
-      			  fs.close(fd);
-      			}
-  	      }); 
-  	    })(); // reader() 
-  	  });
-     } else if (this.value instanceof Data) {
-  	  stream.write(this.value.data);
-  	  stream.write("\r\n");
-  	  callback();
-     } else {
-  	  stream.write(this.value + "\r\n");
-  	  callback();
-  	}
-  }
+
+        var self = this;
+
+        //first write the Content-Disposition
+        stream.write(this.header());
+
+		//Now write out the body of the Part
+        if (this.value instanceof File) {
+            fs.open(this.value.path, 'r+', function (err, fd) {
+                var stats = fs.fstatSync(fd);
+                var bufferSize = stats.size
+                if (err) throw err;
+                var chunkSize = 512;
+                var position = 0;
+                var buf = new Buffer(bufferSize);
+                (function reader () {
+
+                    if ((position + chunkSize) > bufferSize) {
+                        chunkSize = (bufferSize - position);
+                    }
+
+                    fs.read(fd, buf, position, chunkSize, position,  function (er, chunk, buf) {
+                        if (er) callback(err);
+                        stream.write(buf.slice(position, chunkSize + position));
+                        position += chunkSize;
+                        if (position < bufferSize) reader();
+                        else {
+                            stream.write("\r\n")
+                            callback();
+                            fs.close(fd);
+                        }
+                    });
+                })(); // reader()
+            });
+        } else if (this.value instanceof Data) {
+            stream.write(this.value.data);
+            stream.write("\r\n");
+            callback();
+        } else {
+            stream.write(this.value + "\r\n");
+            callback();
+        }
+    }
 }
 
 //Renamed to MultiPartRequest from Request